Google Calendar Api not returning attendee name for directory contacts

Question

I have built a web application that uses a service account linked to my own Google Account. We use Google Apps, so my Google Account is part of a domain. We have a server with shared contacts, so all of our clients are available as contacts for everyone. In my contacts, this group is called 'directory'.

The application retrieves events from the Google Calendar using the Google Api PHP client. It also retrieves attendees inlcuding all details for those attendees. But if the attendee is not within our domain, it will only retrieve the e-mail address. I also want to get the name for that attendee.

These names are in my contacts in the directory group. When I create an event and invite guests, I can retrieve these contacts and it will show the name and mail adress. But when retrieving the attendees via the API it does not show these names.

Is this a restriction of the API? Is there a solution for this?

I do not want to use the Contacts api with a non-service account, because I don't want to give permission everytime. It is not possible to use the Contacts api with a service account as far as I know.

Answer 1

You are correct that a service account won't work with the Contacts API, however you don't have to authorize it every time you use it. You can provide domain-wide delegation with two-legged OAuth 1.0a instead of 2.0. See https://developers.google.com/google-apps/contacts/v3/index#authorizing_requests_to_the_+wzxhzdk8+_service and https://developers.google.com/accounts/docs/OAuth#GoogleAppsOAuth.

Depending on your setup, you can also use the three-legged OAuth 2.0 flow for a single administrator account and save the refresh token. This would let you re-use that authorization without requiring explicit permission again.